Cooperative Effects in Matter and Radiation pp 209-256 | Cite as

# Theory of Fir Superfluorescence

## Abstract

We show that the second quantised theories of superfluorescence (SF) from rod-like geometries and the semiclassical approach based on the Bloch-Maxwell equations are compatible with each other. From the semi-classical theory we show that two regimes of SF are expected according as τSF,the superfluorescence time, exceeds or is exceeded by τE,the photon escape time: τSF τ τE defines the regime of oscillatory SF characterised by a first pulse intensity α τSF^{-2} and a small number of subsequent ringing pulses; τSF ≪ τE defines a regime of steady oscillation characterised by a first pulse intensity α τSF^{−1} and a steady train of similar ringing pulses. Diffraction or other losses from a rod-like geometry damps the ringing in the oscillatory SF regime and single pulse emission without subsequent ringing is possible in this regime. Pulse widths τ_{W} and delays t_{D} depend on damping:ringing intensities depend on this and very significantly on the initial conditions. The two spatially inhomogeneous fields travelling in opposite directions inside a rod damp each other’s ringing. We summarize the difficulties which still prevent the provision of a comprehensive ab initio second quantised theory of SF from extended systems.

## Keywords

Spontaneous Emission Diffraction Loss Semiclassical Approach Steady Oscillation Ringing Pulse## Preview

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## References

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